Expansion joint



Oct. 18, 1938.

J. W. HELTZEL EXPANSION JOINT Filed Dec. 28, 1934 Patented Oct. 18, 1938 UNITED STATESv PATENT OFFICE 2,133,387 ExPANsIoN Jouw'y Joseph William Heltzel, Warren; Ohio Application December za, 1934, serial No. 759,571) l a claims. (ci. 94 1s)` AThe present invention relates to expansion joints for use in road construction to divide the road surface into slabs or blocks and admit the relative movement thereof during expansion and contraction of the road.

In the past, expansion joints were usually con-v structed by placing asphaltic material into a slot in the roadway. This type of joint has been found wanting in that when the road expands a large part of the liquid contained in the-joint is forced upwardly on the roadway, forming a hump. In the present invention the depth .of this' illler may be only approximately one-seventh of the l Another shortcoming of the old type of joint has been that about one-half of the joint material'A consists of solid matter, and when expansion' takes place, the amount of expansion available is only about one-haii' the thickness of the joint material.

An object of the invention is to provide an expansion joint having parts which are slidableone on the other and which are so attached or molded to the adjacent slabs of the roadway as 35' to transfer load pressure from slab to slab, and `maintain the slabs invertical alinement, and effectively exclude foreign solid particles tending to destroy the' flexibility of the joint.

Another object of the invention is to provide 40 an improved expansion joint wherein the members are not only slidably-interlocked one with the other but are also readily interlockd with the adjacent road slabs and wherein means is pro,- vided for preventing filling in of crevices tending to retard the :free 'movement of the sliding members.

Another object is to provide a flexible vyielding joint which will yield and 'act like a hinges in case of undue upward or downward movements 50 causing both adjoining slabs to yield in unison when unusual pressures cause such movements.

A further object'of the invention is to provide an improved method of constructing an expansion joint and placing the filler strip of plastic 55 material in such position that a. relatively small amount of the plastic material is required for sealing the joint 'at the upper surface of the roadway, and provide for its easy removal for refilling.

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto.v j v. In the drawing, wherein like symbols refer to like or corresponding parts throughout the several views:

Figure 1 is a perspective view of a section of roadway inl lcross section taken immediately adjacent an expansion joint constructed and installed according to the present invention; part of"y the roadway being broken away to show the anchors for one of the expansion joint elements.

AFigure 2 is an enlarged sectional view taken transversely through the joint substantiallyon the line 2--2 of Figure 1.

Figure 3 is a similar View but showing'the joint in expanded position as compared with the closed position of Figure 2.

Figure 4 is a'fra'gmentary sectional view taken through one end of the joint 'substantially on th line 4 4 of Figure 3, and showing the end closure meansto exclude solid material from the space br tween the. joint elements.

Figure 5 is a like view showing a modified form o f the end closure.

Figure 6 is a fragmentary sectional view, taken through the roadway at the meeting inner ends of adjacent expansion joints.

Figure '7 is a fragmentary sectional view taken through the lower end of the expansion joint,

provided respectively with flanges I2 and I3 and v A these flanges are disposed to slide upon one another, as shown in Figures 2A and 3. The-smaller or inner channel member, having the web I0 and flanges I2, fits into the open side of the larger channel lmember having the web II and flanges' I3 so that the flanges I3` provide guides for the inner member a'nd upon which the latter may slide to and from the web II of the larger inember. The larger channel member preferably has 'its web I I and its flanges I3 atleast twice as thick as thewcb l0 and angesl2 of the'smaller'inner channel member so that the outer channel member may withstand the strain imposed on it in the transfer of forces between the channel members.

The larger member II is provided upon its outer side, intermediate th.` upper and lower edges of the web II, with a shear bar I4 adapted for embedding in the body portion or material of an adjacent road slab I5 which is molded against the outer side of the web I I in placing the ioint. Suitable anchors I6 are also carried by the web. II and are adapted to be embedded in the material ofl the slab I5 so as to rmly hold the outer or larger channel member to the slab I5 for movement therewith in the expansion and contraction of the slab.

This larger or outer channel member is positioned in the joint preferably ush with the lower face of the slab I5 so that the outer member rests at its lower flange I3 upon the sub-base of the roadway.

The inner or smaller channel member is adapted to receive in its concave or open side of the material of a second adjacent slab II of the roadway and thus shearing tendencies of the inner member is oiiset by the thickness of the enclosed slab material lying between the flanges I2. An anchor I8 is attached to the web I0 and extends from the inner side thereof for embedding in the material of the slab I1 to securely hold the inner channel member to the slab II for independent movement therewith during the expansion and contraction of the slab.

The channel members are of such height, compared to the thickness of the slabs I5 and II, as to provide a slot or space between the abutting portions of the slabs and above the joint to receive a filler I9 of a suitableplastic composition which will be relatively smallin volume and which will readily maintain a closed or filler -joint crevice at the upper surface of the roadway. rhe quantity of the material I9, depending upon the relatively small size of the slot or channel, is such that vwhen the slabs expand and close the joint, as shown in Figure 2, the amount of the plastic material ejected upwardly from the crevice will be relatively small and negligible as compared with the amount of plastic filler used in joints of the present day type and consequently the road surface will1be maintained relatively smooth and without humps of any appreciable size.

An elastic ller element 20, of sponge rubber of the slab I1 with the upper surface of the ller member 20 lying in partagainst the lower side of the adjacent flange I2. The outer end of the filler member 20 abuts the end of the adjacent flange I3 of the outer member while the opposite end of the filler member 20 abuts a shoulder 2| provided in the molding of the material of the slab I1 over and about the member 20.

With this construction, as the relatively slidable and interttin'g channel members contract under pressure of expansion of the slabs I5 and I1, the compressible element or member 20 is reduced in size, as shown in Figure 2, while as soon as the channel members spread apart or expand the compressible member 28 will followv such motion and exclude foreign substances from the path of the lower ange I3 so'thatthe latter will have a relatively free path oi' movement in the expansion and contraction of the joint.

In the modification shown in Figure 'I the "element 23 is omitted and the lower outer flange I3 is beveled as at Ita similar to the upper flange .'joints. in the cross grooves or channels disposed above which faces the plastic filler I9 so as to gradually raise the filler when the channel members are moved toward each other and to thus reduce to a minimum resistance or friction occasioned by this movement. The air space between the webs I0 and II of the channel members is negligible from the standpoint of resistance to the action of the joint and the overlapping flanges I2 and I3 ef fect a desired closure suiilcient for excluding solid particles which 'would otherwise interfere with the free action of the joint.

As shown in Figure 4,' the opposite ends of the channel members may be provided with a closure plate 23 'which may have an anchor 2| at one l,end portionAto engage in one of the slabs, such as the slab I5, while the other end of the closure plate is freely slidable in a recess in the opposite slab II and a compressible ller member 25 may be provided between the end of the plate 23 and the adjacent shoulder of the slab II. A rubber sealing strip 23a may be placed against the inner side of the plate 23 for engagement against the ends of the channel webs I0 and II. This closureplate 23 with its sealing\strip 23a,

-at each end of the space between the Wb's I0 and II, eectually closes the space against ehtrance of solid particles which otherwise might impede the closure movement of the channel members.

A slight modification in the construction of the end closure for the space between the channel members is shown in Figure 5 wherein the inner channel web 28 is shorter than the Width oi' the road and the outer channel web 29 is slightlyv the webs 28 and 29 may move toward and from each other and the plate 3I serves as a guide ,over which the adjacent end of the web 28 may slide. or the like, may be countersunk in the lower face With reference particularly to Figure 6 there is shown the meeting ends of the expansion joints at the central portion of the roadway and wherein the upperfianges I3 of the outer channel member substantially abut and support an overlapping plate 33 forming the bottom of a groove 34 formed 'longitudinally in the surface portion of the roadway and in which is placed or poured a suitable ller material or strip 35. The material 35 may be of a softer vor thinner consistency at the bottom of the groove 3l, as shown, while the upper orl surface portion of the material is of a harder character so as to withstand wear and offer the necessary resistance for maintaining the 'crevice closed at all times.

The plate 33 may be of steel or the like so as to hold the softer filling material from flowing down between the adjacent ends of the expansion This type of iler may, of course, be used the expansion joint.

With reference now to Figure 8 the groove provided in the surface portion Ao! the roadway is shown before the molding strip 33 is removed.

\The molding strip 36 may be formed in one or /more pieces and is shown in Figure 8 as comprising two parts, 36 and 36a, so as to take care of the flaring or undercut formation of the groove immediately above the expansion joint, shown in Figures 2 and 3. The strips 36 and 36a may be withdrawn from the joint and the desired filling material poured into the joint above the channel members. These molding strips are held in place by stakes or the like in any suitable manner until the concrete or other material used flows in about the intertting channels and about the opposite sides of the molding strips.

'Ihis expansion joint thus not only provides a relatively small crevice or opening at the top of the joint for the plastic filler I9 but also effec tively transfers load pressure from one slab to the other by lvirtueof the overlapping engagement of the fianges'l Zand I3. Further, these 'flanges effectively hold the slabs I5 `and I1 in true vertical alinement and prevent distortion or movement of the slabs out of alinement during their relative movements,lparticularly where 'gthe outer channel is of twice the thickness of the .inner channel.

The method of installing this joint in a road- 'way comprises the assembly of the channel members in interfitting relation and disposing them in upright position. 'Ihe lower ller member 20, when used, is placed in position beneath the lower flange I2 and against the end of the lower flange I3, resting upon the surface of the sub-base of the road. A suitable mold strip '236 and 36a is seated upon the upper endpof the interfitting channel members and the upper surface material of the roadway is poured in place .fand is filled in against the outer side of the web II of the large channel member, about the anchors I6 and about the shear bar I4. The pour- ,ing of the material causes the, material to flow into the open side of the inner channel. member and about the anchors I8 thereof. Stakes may be driven into the soil to hold the members in place until the concrete is poured around the joint members and may be used and removed as the concrete is poured around the members.

-The material of the slab I1 also is shaped about the expansion' member 20 to provide the shoulder 2| and thus form a recess or pocket in the.

slab for the expansion member. At the same time the lateral or side closure plates 23 are held in place by forms or the like against the opposite ends of the channel members so. that when the material of the slabs I and I1 are poured in place they will provide recesses defined by the end portions of the closure plate 23 and itsexpansion member 25.

The ller strip 3B is then removed from the relatively small and shallow slot or crevice at the top of the joint and the plastic filler material I9 is poured in. One advantage of this construction is that a commercial channel may be used for the inner member as well as for the outer member. The flanges or legs may be reduced as well as the webs of the channels. The desired slidable interiitting of the channels'may thus be provided and'l vit will be noted that the legs or flanges of bothehannel members extend in the same direction and that the smaller channel` is nested within the open side ofthe larger channel.

It will be noted also that the flanges I3 of the outer channel are at all times abutting against the opposite upper and lower edges ofthe web I0 of the small channel so that there is a substantially direct transfer of load pressure from one channel to the other and the danger of flexing or'bending the channels is reduced to a minimum. The arrangement is such that the crevice or groove at the top of thejoint is made relatively narrow and shallow and may be filled with tar, asphalt or the like so as to effectively close the top of the joint and maintain a substantially smooth and uninterrupted surface level to the roadway.

To insure sealing the space between the channel members, the lower leg I3 of the outer channel member may have a coating or layer 3l of filler material on the inner or upper side thereof and this layer 31, being yieldable, is capable of expansion and contraction or displacement sufliciently to offer practically no resistance to the relative movements of the channel members.

It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modications being restricted only by the scope of the following claims.

What is claimed isz- 1. An expansion joint comprising a pair of interiitting channel members with the outer side of the inner member facing the inner side of the outer member and said members being relatively slidable, means for anchoring said members independently to adjacent road surface slabs, an

expansible filler element disposed against the 2. A roadway or concrete structure, having an expansion joint, consisting of inner and outer channel structures having right angle flanges at top and bottom, one sldably within the other with flanges of each channel structure in same direction and a yielding'ller substance placed against the edge of the top flange of the outer channel to yield in the path of the flanges of the outer channel when in movement.

3. In an expansion joint, a pair of interfitting channel members yeach having right angle flanges at top and bottom, both placed with flanges in the same direction,`road slabs molded about the outer sides of said members for carrying the members therewith and `said members adapted to slide one within the other upon the expansion and contraction of the road slabs, said road slabs eX- tending higher than the members and having their adjacent end portions above the members spaced apart to provide a groove above the members' and said groove having a bottom width substantially` equal to the depth of the flanges of the channel members and being reduced in width at the surface portion of the roadway, and a flexble ller disposed in the groove for sealing the same above the channel members.

bers for excluding foreign particles from the space between the channel members.

5. An expansionl joint, comprising outer and inner channel members disposed transversely between the abutting ends of slabs in a roadway, each of said members being anchored to its adjacent slab and with the flanges of said members extending in the same direction and each of said members having a lwidth less than the thickness of the slabs, the upper anges of said members being disposed below the top surfaces of said slabs, said outer channel member being heavier than said inner channel member whereby when a vehicle crosses the joint from the slab anchor to the heavier outer, channel member, the loadwill be transferred from said slab to the outer heavier channel member through the upper ilange thereof to the inner channel member and to the adjoining slab and when the vehicle passes in the opposite direction the load may be transferred from said other adjacent slab through the inner channel member to the lower iiange of said heavier outer channel member to said first slab.

6. An expansion joint, comprising a pair of slidably intertting channel members having overlapping rightangular ilanges extending in the same direction, said channel members disposed vertically in a roadway with the lower flange of the outer member seated directly on the subsurface of the roadway and with the upper ange of the outer member spaced a short distance below the upper surface of the roadway for directly transmitting the load and shock on the joint to the sub-surface, means for anchoring the channel members to their respective adjacent portions of the roadway, a sealing substance disposed above the channels and between the adjacent portions of the roadway, and a sealing substance on the inner side of the lower flange of the outer member.

7. An expansion joint for roads, comprising a pair of road surface slabs, a pair of slidably intertting channel members disposed between the ends of the slabs having overlapping top and bottom anges extending in the same direction and with the bottom ilange of the outer member seated on the sub-surface of the roadway to directly support both members thereon, said channel members being. vertically disposed and terminating a short distance below the upper surface of the roadway with theinner member embracing the end of its adjacent road slab, means for anchoring the members to their respective ends of the slabs, a yieldable i'lller substance disposed above the members between the adjacent ends of the slabs, and a yieldable filler substance on the inner side of' the lower flange of the outer member.

8. An expansion joint comprising inner and outer interfitting relatively slidable channel members having right angled top and bottom ilanges and adapted to be embedded in the ends of ad' 

